System and method for connecting a call

ABSTRACT

A system and method connects a call in a broadband system using the asynchronous transfer mode protocol for switching. Calls are connected over a SONET ring that has SONET multiplexers coupled by SONET paths. The SONET multiplexers are adapted to add calls to, and drop calls from, the SONET ring. An ATM cross connect system that has ATM cross connect devices is coupled to the SONET ring. The ATM cross connect devices provide provisioned ATM connections over the SONET ring. ATM interworking units are coupled to the ATM cross connect system. The ATM interworking units interwork calls with selected ATM connections in response to control messages. The selected ATM connections are provisioned between the ATM interworking units by the ATM cross connect system over the SONET ring. A signaling processor system receives call signaling for the calls, processes the call signaling to select the ATM connections for the calls, and sends the control messages to the selected ATM interworking units. The control messages designate the selected ATM connections.

RELATED APPLICATIONS

Not Applicable

FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

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MICROFICHE APPENDIX

Not Applicable

FIELD OF THE INVENTION

The present invention relates to the field of telecommunications callswitching and transport.

BACKGROUND OF THE INVENTION

Broadband systems are being developed and implemented. Broadband systemsprovide telecommunications providers with many benefits, includinggreater bandwidth, more efficient use of bandwidth, and the ability tointegrate voice, data, and video communications. These broadband systemsprovide callers with increased capabilities at lower costs.

Switches and other communication devices use broadband systems, such asa synchronous optical network (SONET) ring or a synchronous digitalhierarchy (SDH) system, to connect calls to other switches andcommunication devices. The switches, for example, determine how a callis to be connected and control the switching over the broadband system.In addition, switches, such as tandem switches, are used to concentratetelecommunication traffic between networks, switches, and othercommunication devices.

However, controlling call switching and connection functions fromswitches and some other communication devices is expensive. Moreover,intelligent network routing and processing functions are limited. Inaddition, conventional switching systems do not provide highly efficientcall concentration and call routing in networks such as metropolitanarea networks (MANs). Therefore, there is a need for a system that moreefficiently and more easily provides connections for switches and othercommunications devices over broadband networks, such as the SONET ringor the SDH system. An effective system is needed that can controlswitching and call connections between system devices on a call-by-callbasis in an asynchronous transfer mode (ATM) environment.

SUMMARY OF THE INVENTION

The present invention comprises a broadband system for connecting callsthat use time division multiplexing. The system comprises a SONET ringthat is adapted to interconnect devices coupled to the SONET ring. TheSONET ring comprises SONET multiplexers coupled by SONET paths. TheSONET multiplexers are adapted to add calls to, and drop calls from, theSONET ring. The system further comprises an ATM cross connect systemthat is coupled to the SONET ring. The ATM cross connect systemcomprises ATM cross connect devices. The ATM cross connect devices areadapted to provide provisioned ATM connections over the SONET ring. Thesystem further comprises a plurality of ATM interworking units that arecoupled to the ATM cross connect system. The ATM interworking units areadapted to interwork calls with selected ATM connections in response tocontrol messages. The selected ATM connections are provisioned betweenselected ATM interworking units by the ATM cross connect system over theSONET ring. The system also comprises a signaling processor system thatis adapted to receive call signaling for the calls, to process the callsignaling to select the ATM connections for the calls, and to send thecontrol messages to the selected ATM interworking units. The controlmessages designate the selected ATM connections.

The present invention also comprises a broadband system for connecting acall having a time division multiplex format. The system comprises aSONET ring that is adapted to interconnect devices coupled to the SONETring. The SONET ring comprises a plurality of SONET multiplexers thatare coupled by a SONET path. The SONET multiplexers are adapted to addthe call to, and drop the call from, the SONET ring. The system furthercomprises an ATM cross connect system comprising a plurality of ATMcross connect devices coupled to the SONET multiplexers. The ATM crossconnect devices are adapted to provide a provisioned ATM connectionthrough the SONET multiplexers over the SONET path. Still further, thesystem comprises a plurality of ATM interworking units coupled to theATM cross connect devices. The ATM interworking units are adapted tointerwork the call with the provisioned ATM connection in response tocontrol messages. The provisioned ATM connection is provisioned by theATM cross connects between the ATM interworking units through the SONETmultiplexers over the SONET ring. The system also comprises a signalingprocessor system that is adapted to receive call signaling for the call,to process the call signaling to select the ATM connection for the call,and to send the control messages to the ATM interworking units. Thecontrol messages designate the selected ATM connection.

The present invention also is directed to a broadband system forconnecting a call over a SONET ring that is adapted to interconnectdevices coupled to the SONET ring. The call has a time divisionmultiplex format and has user communications and call signaling. Thesystem comprises a SONET multiplexer that is coupled to the SONET ring.The SONET multiplexer is adapted to add the call to the SONET ring. Thesystem also comprises an ATM cross connect that is coupled to the SONETmultiplexer. The ATM cross connect is adapted to provide a provisionedATM connection through the SONET multiplexer over the SONET ring. Thesystem also comprises an ATM interworking unit coupled to the ATM crossconnect. The ATM interworking unit is adapted to interwork the usercommunications with the ATM connection in response to a control message.The ATM connection is provisioned by the ATM cross connect from the ATMinterworking unit through the SONET multiplexer over the SONET ring. Thesystem further comprises a signaling processor that is adapted toprocess the call signaling to select the ATM connection for the callfrom among a plurality of connections and to send the control message tothe ATM interworking unit designating the ATM connection.

Still further, the present invention is directed to a broadband systemfor connecting a call over a SONET ring that is adapted to interconnectdevices coupled to the SONET ring. The call has call signaling and usercommunications. The system comprises a signaling processor that isadapted to receive the call signaling for the call, to process the callsignaling to select an ATM connection for the call, and to send acontrol message designating the selected ATM connection. The system alsocomprises an ATM interworking unit that is adapted to receive thecontrol message from the signaling processor, to receive the usercommunications, and to interwork the use communications for the callbetween a non-ATM connection and the selected ATM connection in responseto the control message. The system includes a SONET multiplexer that isadapted to provide access to the SONET ring for the selected ATMconnection. The system also includes an ATM cross connect that isadapted to provision the selected ATM connection from the ATMinterworking unit through the SONET multiplexer over the SONET ring. Thecall is transported over the provisioned selected ATM connection fromthe ATM interworking unit, though the ATM cross connect, through theSONET multiplexer, and over the SONET ring.

Further still, the present invention is directed to a broadband systemfor connecting a call having a time division multiplex format over abroadband ring. The call has call signaling and user communications. Thesystem comprises a signaling processor that is adapted to receive thecall signaling for the call, to process the call signaling to select aselected connection for the call from among a plurality of connections,and to send the control message designating the selected connection. Thesystem comprises an add/drop multiplexer that is adapted to provide thecall access to the broadband ring. The system also comprises a crossconnect that is adapted to provision the selected connection through theadd/drop multiplexer over the broadband ring. The system furthercomprises an interworking unit that is adapted to receive the usercommunications and to receive the control message from the signalingprocessor and, in response thereto, to interwork the user communicationsfor the call to asynchronous transfer mode cells that identify theselected connection. The interworking unit maps the asynchronoustransfer mode cells to broadband frames and transports the broadbandframes over the selected connection. The connection is provisioned bythe cross connect from the interworking unit through the add/dropmultiplexer over the broadband ring.

The present invention is further directed to a method for connecting acall that uses time division multiplexing. The method comprisesprovisioning an ATM connection over a SONET ring. The method furthercomprises receiving and processing call signaling to select the ATMconnection for the call from among a plurality of connections. A controlmessage is transported designating the selected ATM connection for thecall. The control message is received and, in response thereto, the callis interworked to the selected ATM connection. The call is transportedon the selected ATM connection over the SONET ring.

The present invention is further directed to a method for connecting acall that uses time division multiplexing. The method comprisesprovisioning an ATM connection over a SONET ring between a first ATMinterworking unit and a second ATM interworking unit. The methodcomprises receiving and processing call signaling in a signalingprocessor to select the ATM connection for the call from among aplurality of connections. A control message is transported from thesignaling processor designating the selected ATM connection for thecall. The control message is received in the first ATM interworking unitand, in response thereto, the call is interworked from a first non-ATMconnection with the selected ATM connection. The call is transported onthe selected ATM connection over the SONET ring to the second ATMinterworking unit. The call is interworked in the second interworkingunit from the selected ATM connection to a second non-ATM connection.

In addition, the present invention is directed to a system forconnecting a call in a broadband ring. The call has user communicationsand call signaling. The user communications are interworked toasynchronous transfer mode cells and then mapped to broadband frames.The system transports the broadband frames on a selected connection overthe broadband ring. The selected connection is a virtual connection. Thesystem comprises a signaling processor that is adapted to receive thecall signaling, to process the call signaling to select a secondconnection, and to transport a control message that designates theselected second connection. Included is an add/drop multiplexer that isadapted to drop the broadband frames for the call from the broadbandring. A cross connect also is included. The cross connect is adapted toprovide the provisioned selected connection from the broadband ringthrough the add/drop multiplexer. The system further includes aninterworking unit that is adapted to receive the broadband frames forthe call from the selected connection through the add/drop multiplexerand through the cross connect. The interworking unit receives thecontrol message from the signaling processor, converts the broadbandframes to user communications having a communication format, andtransports the user communications over the selected second connection.

In another aspect, the present invention is a system for connecting acall in a broadband system. The call has user communications and callsignaling. The system comprises a first communication device that isadapted to transport the call and a second communication device that isadapted to receive the call. The system comprises a signaling processorthat is adapted to receive the call signaling, to process the callsignaling to select a first connection and a second connection, totransport a first control message that designates the selected firstconnection, and to transport a second control message that designatesthe selected second connection. The first selected connection comprisesa virtual path over a broadband path. The virtual path is provisionedover the broadband path in the broadband system. The selected secondconnection connects to the second communication device. The systemfurther comprises a first interworking unit that is adapted to receivethe user communications in a communication format, to receive the firstcontrol message from the signaling processor, to convert the usercommunications to asynchronous transfer mode cells that identify theselected first connection that was designated in the first controlmessage, and to transport the asynchronous transfer mode cells. Alsocomprising the system is a first cross connect that is adapted toreceive the asynchronous transfer mode cells from the first interworkingunit and to cross connect the asynchronous transfer mode cells to thevirtual path for the selected first connection. A first add/dropmultiplexer is included to receive the asynchronous transfer mode cellsfrom the first cross connect and to add the asynchronous transfer modecells to the broadband path for the selected first connection.

The system further comprises a second add/drop multiplexer that isadapted to receive the asynchronous transfer mode cells on the broadbandpath and to drop the asynchronous transfer mode cells from the broadbandpath. A second cross connect is in the system to receive theasynchronous transfer mode cells from the second add/drop multiplexerand to cross connect the asynchronous transfer mode cells according tothe provisioned virtual path. The system includes a second interworkingunit that is adapted to receive the asynchronous transfer mode cellsfrom the second cross connect and to receive the second control messagefrom the signaling processor. The second interworking unit converts theasynchronous transfer mode cells to user communications having acommunication format and transports the user communications to thesecond communication device over the selected second connection.

In still another aspect, the present invention is directed to a systemfor connecting a call in a broadband system. The call has usercommunications and call signaling. The system comprises a signalingprocessor and a broadband interface. The signaling processor is adaptedto receive the call signaling and to process the call signaling toselect a connection. The signaling processor transports a controlmessage that designates the selected connection. The selected connectioncomprises a virtual path over a broadband ring in the broadband system.The virtual path is provisioned over the broadband ring. The broadbandinterface is adapted to receive the user communications in acommunication format and to receive the control message from thesignaling processor. The broadband interface interworks the usercommunications to asynchronous transfer mode cells that identify theselected connection and maps the asynchronous transfer mode cells tobroadband frames. The broadband interface transports the broadbandframes on the provisioned virtual path over the broadband ring.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a broadband metropolitan area network witha plurality of broadband interfaces of the present invention.

FIG. 2 is a block diagram of components of a first broadband interfaceand components of a second broadband interface.

FIG. 3 is a block diagram of a broadband interface in which multipleinterworking units are attached to a cross connect.

FIG. 4 is a block diagram of a broadband metropolitan area network witha plurality of broadband interfaces each attached to a signalingprocessor which communicate with a signal transfer point.

FIG. 5 is a functional diagram of an asynchronous transfer modeinterworking unit for use with a synchronous optical network system inaccordance with the present invention.

FIG. 6 is a functional diagram of an asynchronous transfer modeinterworking unit for use with a synchronous digital hierarchy system inaccordance with the present invention.

FIG. 7 is a block diagram of a signaling processor constructed inaccordance with the present system.

FIG. 8 is a block diagram of a data structure having tables that areused in the signaling processor of FIG. 7.

FIG. 9 is a block diagram of additional tables that are used in thesignaling processor of FIG. 8.

FIG. 10 is a table diagram of a trunk circuit table used in thesignaling processor of FIG. 8.

FIG. 11 is a table diagram of a trunk group table used in the signalingprocessor of FIG. 8.

FIG. 12 is a table diagram of an exception circuit table used in thesignaling processor of FIG. 8.

FIG. 13 is a table diagram of an automated number index table used inthe signaling processor of FIG. 8.

FIG. 14 is a table diagram of a called number table used in thesignaling processor of FIG. 8.

FIG. 15 is a table diagram of a routing table used in the signalingprocessor of FIG. 8.

FIG. 16 is a table diagram of a treatment table used in the signalingprocessor of FIG. 8.

FIG. 17 is a table diagram of a message table used in the signalingprocessor of FIG. 8.

DETAILED DESCRIPTION

Telecommunication systems have a number of communication devices inlocal exchange and interexchange environments that interact to providecall services to customers. Both traditional services and resources andintelligent network (IN) services and resources are used to process,route, or connect a call to a designated connection.

A call has call signaling and user communications. The usercommunications contain the caller's information, such as a voicecommunication or data communication, and they are communicated over aconnection. Call signaling contains information that facilitates callprocessing, and it is communicated over a link. Call signaling, forexample, contains information describing the called number and thecalling number. Examples of call signaling are standardized signaling,such as signaling system #7 (SS7), C7, integrated services digitalnetwork (ISDN), and digital private network signaling system (DPNSS),which are based on ITU recommendation Q.933.

A call can be transported to or from a communication device. Acommunication device can be, for example, customer premises equipment(CPE), a service platform, a switch, or any other device capable ofinitiating, handling, or terminating a call. Customer premises equipmentcan be, for example, a telephone, a computer, a facsimile machine, or aprivate branch exchange. A service platform can be, for example, aservice platform or any other enhanced platform that is capable ofprocessing calls.

Communications devices in both traditional and intelligent systems canuse a variety of protocols and methods to achieve a connection for acall or to complete call processing. For example, CPE can be connectedto a switch using a time division multiplex (TDM) format, such as superframe (SF) or extended superframe (ESF). The ESF connection allowsmultiple devices at the customer site to access the local switch andobtain telecommunication services.

Also, communication devices, such as telephones, are likely connected toa remote digital terminal, and the connection typically carries analogsignals over twisted pair wires. The remote digital terminals provide adigital interface between the telephones and a local switch byconverting the analog signals from the telephones into a multiplexeddigital signal to be transferred to the local switch. A common standardfor the connection between the remote digital terminal and the localswitch is provided in Bellcore Reference GR-TSY-000303 (GR-303).

In addition, communications devices use broadband protocols, such asbroadband-integrated services digital network (B-ISDN). Broadbandsystems provide greater bandwidth than narrowband systems for calls, inaddition to providing digital processing of the calls. B-ISDN provides acommunication device with a digital connection to a local switch orother device. The B-ISDN loop provides more bandwidth and control than aconvention local loop. The European implementation of B-ISDN and otherbroadband protocols can also be used.

Communication devices can use circuit-based connections for calls. Forexample, digital signal (DS) level communications, such as digitalsignal level 3 (DS3), digital signal level one (DS1), and digital signallevel zero (DS0) are conventional circuit-based connections. Europeanlevel four (E4), European level three (E3), European level one (E1),European level zero (E0), and other European equivalent circuit-basedconnections also are used.

High speed electrical/optical transmission protocols also are used bycommunications devices for switching and signaling. The synchronousoptical network (SONET) protocol, which is used primarily in NorthAmerica, and the synchronous digital hierarchy (SDH) protocol, which isused primarily in Europe, are examples of high speed electrical/opticalprotocols. The SONET and SDH protocols describe the physical media andtransmission protocols through which the communications take place.

The SONET and SDH protocols define a broadband frame structure for SONETand SDH communication signals. Multiple frames travel in thecommunication signals. Each frame consists of overhead and payload. Theoverhead containes operations, administration, maintenance, andprovisioning infromation, such as framing information, error correctioninformation, and pointer information. The payload contains the usercommunications information that is carried in the frame by thecommunication signal. The payload is comprised of payload componentsthat are mapped into the frames. For example, user communications from aDS1, an E1, or an asynchronous transfer mode (ATM) connection may bemapped into the broadband frames. Thus, in a SONET system, the usercommunications are mapped to SONET frames. In an SDH system, usercommunications are mapped to SDH frames.

SONET includes optical transmission of optical carrier (OC) signals andelectrical transmission of synchronous transport signals (STSs). SONETsignals transmit at a base rate of 51.84 Mega-bits per second (Mbps) foroptical carrier level one (OC-1) and synchronous transport signal levelone (STS-1). Also transmitted are multiples thereof, such as an STSlevel three (STS-3) and an OC level three (OC-3) at rates of 155.52Mbps, an STS level twelve (STS-12) and an OC level twelve (OC-12) atrates of 622.08 Mbps, an STS level forty-eight (STS-48) and an OC levelforty-eight (OC-48) at rates of 2,488.32 Mbps, and fractions thereof,such as a virtual tributary group (VTG) at a rate of 6.912 Mbps.

SDH includes transmission of optical synchronous transport module (STMO) signals and electrical synchronous transport module (STM E) signals.SDH signals transmit at a base rate of 155.52 Mbps for synchronoustransport module level one electrical and optical (STM-1 E/O). Alsotransmitted are multiples thereof, such as an STM level fourelectrical/optical (STM-4 E/O) at rates of 622.08 Mbps, an STM levelsixteen electrical/optical (STM-16 E/O) at rates of 2,488.32 Mbps, andfractions thereof, such as a tributary unit group (TUG) at a rate of6.912 Mbps.

ATM is one technology that is being used in conjunction with SONET andSDH to provide broadband call switching and call transport fortelecommunication services. ATM is a protocol that describescommunication of user communications in ATM cells. Because cells areused in the protocol, calls can be transported on demand forconnection-oriented traffic or connectionless-oriented traffic,constant-bit traffic or variable-bit traffic, and between equipment thateither requires timing or does not require timing.

Some ATM systems handle calls over switched virtual paths (SVPs) andswitched virtual circuits (SVCs). The virtual nature of ATM allowsmultiple communication devices to use a physical communication line atdifferent times. This type of virtual connection more efficiently usesbandwidth, and thereby provides more cost efficient transport forcustomer calls, than permanent virtual circuits (PVCs) or otherdedicated circuits.

The ATM system is able to connect a caller from an origination point toa destination point by selecting a connection from the origination pointto the destination point. The connection contains a virtual path (VP)and a virtual channel (VC). A VC is a logical connection between two endpoints for the transfer of ATM cells. A VP is a logical combination ofVCs. The ATM system designates the selected connection by specifying avirtual path identifier (VPI) that identifies the selected VP and avirtual channel identifier (VCI) that identifies the selected VC withinthe selected VP. Because many ATM connections are uni-directional,bi-directional communications in an ATM system usually require companionVPIs/VCIs.

An ATM system may be configured to transmit ATM cells over a SONETbroadband system or an SDH broadband system. The ATM cells are mappedinto the payload of the SONET frames or the SDH frames and transportedover a broadband path, such as a SONET pipe or an SDH pipe. Typicallythe SONET and SDH systems are configured in a ring topology that canprovide redundant and alternate transmission paths for calls.

The present invention efficiently and easily provides connections andswitching for switches and other communication devices over a broadbandsystem. The present invention provides call connections by using ATMover a SONET broadband system or an SDH broadband system. The ATM systemprovides robust switching functions at an affordable cost.

FIG. 1 illustrates the broadband system 102 of the present invention.The broadband system 102 concentrates and switches telecommunicationcall traffic between networks, switches, and elements of the broadbandsystem. The broadband system 102 allows switches and other communicationdevices to connect to each other without a direct connection betweeneach switch and communication device. The broadband system 102 may be,for example, a broadband metropolitan area network (BMAN).

The broadband system 102 comprises a signaling processor 104 and aplurality of broadband interfaces, such as a first broadband interface106, a second broadband interface 108, a third broadband interface 110,a fourth broadband interface 112, a fifth broadband interface 114, and asixth broadband interface 116. It will be appreciated that the broadbandsystem 102 may have a greater or a fewer number of broadband interfaces.

The broadband interfaces 106, 108, 110, 112, 114, and 116 are connectedthrough a series of connections. Thus, the first broadband interface 106is connected to the second broadband interface 108 through a connection118. The second broadband interface 108 is connected to the thirdbroadband interface 110 through a connection 120. The third broadbandinterface 110 is connected to the fourth broadband interface 112 througha connection 122. The fourth broadband interface 112 is connected to thefifth broadband interface 114 through a connection 124. The fifthbroadband interface 114 is connected to the sixth broadband interface116 through a connection 126. The sixth broadband interface 116 isconnected to the first broadband interface 106 through a connection 128.The broadband interfaces 106, 108, 110, 112, 114, and 116 and theconnections 118, 129, 122, 124, 126, and 128 form a broadband ring. Eachof the broadband interfaces 106, 108, 110, 112, 114, and 116 is linkedto the signaling processor 104 through a link 130, 132, 134, 136, 138,and 140, respectively.

Any broadband interface may reach any other broadband interface in thebroadband ring. For example, the first broadband interface 106 mayconnect to the fifth broadband interface 114 by connecting through theconnection 128, the sixth broadband interface 116, and the connection126.

Typically, the connections 118, 120, 122, 124, 126, and 128 are ATMVPIs/VCIs connections that are provisioned over SONET or SDH broadbandpaths. For example, the connections 118, 120, 122, 124, 126, and 128 maybe VPIs/VCIs that are provisioned over OC-48 pipes. The broadbandinterfaces 106, 108, 110, 112, 114, and 116 and the SONET or SDHbroadband paths containing the provisioned virtual connections 118, 120,122, 124, 126, and 128 form a SONET ring or an SDH ring.

Each of the broadband interfaces 106, 108, 110, 112, 114, and 116 may beconnected to a switch or to another communication device. In thebroadband system 102 of the present invention, the first broadbandinterface 108 is connected to a first communication device 142 through aconnection 144. The second broadband interface 108 is connected to asecond communication device 146 through a connection 148. The thirdbroadband interface 110 is connected to a first interexchange carrier(IXC) 150 through a connection 152. The fourth broadband interface 112is connected to an incumbent local exchange carrier (ILEC) 154 through aconnection 156. The fifth broadband interface 114 is connected to acompetitive local exchange carrier (CLEC) 158 through a connection 160.The sixth broadband interface 116 is connected to a second IXC 162through a connection 164. The signaling processor 104 is linked to thefirst communication device 142 through a link 166, to the secondcommunication device 144 through a link 168, to the first IXC 150through a link 170, to the ILEC 154 through a link 172, to the CLEC 158through a link 174, and to the second IXC 162 through a link 176.

The connections 144, 148, 156, and 160 may be any connection thatcarries circuit-based traffic. Typically, these are time divisionmultiplex (TDM) connections, such as DS3 or DS1 connections. Typically,the common DS0 used for traditional voice calls is embedded within theDS3 or DS1. The connections 152 and 164 may be either TDM connections,such as DS3 or DS1 connections, or broadband path connections, such asOC-48 connections that carry ATM traffic.

Connections are used to transport user communications and other deviceinformation between communication devices and between the elements anddevices of the broadband system 102. The term "connection" as usedherein means the transmission media used to carry user communicationsbetween the elements of the broadband system 102 or between thebroadband system 102 and other communication devices and elements. Forexample, a connection could carry a user's voice, computer data, orother communication device data. A connection can be associated witheither in-band communications or out-of-band communications.

Links are used to transport call signaling and control messages. Theterm "link" as used herein means a transmission media used to carry callsignaling and control messages. For example, a link would carry callsignaling or a device control message containing device instructions anddata. A link can carry, for example, out-of-band signaling such as SS7,C7, ISDN, B-ISDN, GR-303, local area network (LAN), or data bus callsignaling. A link can be, for example, an AAL5 data link, UDP/IP,ethernet, or DS0 over T1. In addition, a link, as shown in the figures,can represent a single physical link or multiple links, such as one linkor a combination of links of ISDN, SS7, TCP/IP, or some other data link.The term "control message" as used herein means a control or signalingmessage, a control or signaling instruction, or a control or signalingsignal, whether proprietary or standardized, that conveys informationfrom one point to another.

Those skilled in the art are aware that large networks have many morecomponents than those that are shown in FIG. 1. For example, there maytypically be a multitude of switches and communication devices connectedthrough the broadband system 102. Those skilled in the art willappreciate that a signal transfer point (STP) may be used to transfersignaling among the various components. The number of components shownon FIG. 1 has been restricted for clarity. The invention is fullyapplicable to a large network or a small network.

The signaling processor 104 is a signaling platform that can receive andprocess signaling. Based on the processed signaling, the signalingprocessor 104 selects processing options, connections, or resources forthe user communications and generates and transmits control messagesthat identify the communication device, processing option, service, orresource that is to be used. The signaling processor 104 also selectsvirtual connections and circuit-based connections for call routing andgenerates and transports control messages that identify the selectedconnections. The signaling processor 104 can process various forms ofsignaling, including ISDN, SS7, and C7. A preferred signaling processoris discussed in detail below.

The broadband interfaces 106, 108, 110, 112, 114, and 116 transporttelecommunication traffic between circuit-based connections and virtualconnections, between circuit-based connections and other circuit-basedconnections, or between virtual connections and other virtualconnections. The broadband interfaces 106, 108, 110, 112, 114, and 116place telecommunication traffic onto the broadband paths of thebroadband system 102 and take telecommunication traffic from thebroadband paths of the broadband system. Likewise, the broadbandinterfaces 106, 108, 110, 112, 114, and 116 receive telecommunicationtraffic from circuit-based systems and transfer telecommunicationtraffic to circuit-based systems.

The broadband interfaces 106, 108, 110, 112, 114, and 116 provideswitching and intelligent network functions for calls. For example, thebroadband interfaces 106, 108, 110, 112, 114, and 116, together with thesignaling processor 104, connect calls from one communication device toanother communication device.

The communication devices 142 and 146 each comprise CPE, a serviceplatform, a switch, a remote digital terminal, or any other devicecapable of initiating, handling, or terminating a call. CPE can be, forexample, a telephone, a computer, a facsimile machine, or a privatebranch exchange. A service platform can be, for example, a serviceplatform or any other enhanced platform that is capable of processingcalls. A remote digital terminal is a device that concentrates analogtwisted pairs from telephones and other like devices and converts theanalog signals to a digital format known as GR-303.

The first and second IXCs 150 and 162 comprise communication devicesthat can transport, receive, and handle calls. The first and second IXCs150 and 162 may be connected to other IXCs, local exchange carriers(LECs), or other communication devices.

The ILEC 154 and the CLEC 158 each comprise switches that transport,receive, and handle calls. The ILEC 154 is an established local network.The CLEC 158 is a newer local network that is allowed to compete withthe established local network. The ILEC 154 and the CLEC 158 may be, forexample, class 4 tandem switches, class 5 switches, or class 4/5switches. The switches shown on FIG. 1 are well known circuit switcheswith examples being the Nortel DMS-250 or the Lucent 5ESS.

The system of FIG. 1 operates as follows for a call that is transportedbetween the CLEC 158 and the ILEC 154 through a SONET ring. The CLEC 158transports call signaling to the signaling processor 104 over the link174 and transports user communications in a TDM format to the fifthbroadband interface 114 over the connection 160.

The signaling processor 104 receives the call signaling and processesthe call signaling to determine connections for the call. The signalingprocessor 104 selects a first connection 124 and a second connection156. The selected first connection 124 is a SONET/ATM connection havingan ATM VPI/VCI virtual connection that is provisioned over a SONET OClevel broadband path on the SONET ring between the fourth broadbandinterface 112 and the fifth broadband interface 114. For example, theselected first connection may be a VPI/VCI provisioned over an OC-48span. The selected second connection 156 is a TDM connection. Thesignaling processor 104 transports a control message over the link 138to the fifth broadband interface 114 identifying the selected firstconnection 124. The signaling processor 104 also transmits a controlmessage over the link 136 to the fourth broadband interface 112identifying the selected second connection 156.

The fifth broadband interface 114 receives the control message from thesignaling processor 104 and the user communications from the CLEC 158.The fifth broadband interface 114 converts the TDM formatted usercommunications to ATM cells that identify the selected first connection124 and maps the ATM cells to SONET frames. The fifth broadbandinterface 114 places the SONET frames on the virtual connection of thedesignated SONET path for the selected first connection 124 so that theyare transported to the fourth broadband interface 112 over the SONETring.

The fourth broadband interface 112 receives the control message from thesignaling processor 104 and receives the SONET frames over the selectedfirst connection 124. The fourth broadband interface 112 drops the SONETframes from the SONET ring and then maps the SONET frames to the ATMcells. The fourth broadband interface 112 converts the ATM cells to TDMformatted user communications and transports the user communications tothe ILEC 154 over the selected second connection 156.

It will be appreciated that a call may be connected from the ILEC 154and to the CLEC 158 in the same manner. Alternatively, a call may beconnected between the ILEC 154 and the first IXC 105, the ILEC 154 andthe second communication device 146, or the ILEC 154 and the firstcommunication device 142. In fact, a call may be connected between anyof the elements in the broadband system 102.

FIG. 2 illustrates the components of the first broadband interface 106and the second broadband interface 108. The first broadband interface106 and the second broadband interface 108 are representative ofbroadband interfaces in the broadband system 102.

The first broadband interface 106 is comprised of a first interworkingunit 202, a first cross connect 204, and a first ring terminal, such asa first add/drop multiplexer (ADM) 206. The first cross connect 204 isconnected to the first interworking unit 202 through a connection 208and to the first ADM 206 through a connection 210.

The first interworking unit 202 interworks traffic between variousprotocols. Preferably, the first interworking unit 202 interworksbetween ATM traffic and non-ATM traffic. The first interworking unit 202operates in accordance with control messages received from the signalingprocessor 104 over the link 130. These control messages are typicallyprovided on a call-by-call basis and typically identify an assignmentbetween a DS0 and a VPI/VCI for which user communications areinterworked.

Thus, the first interworking unit 202 converts TDM formatted usercommunications to ATM cells that identify virtual connections selectedby the signaling processor 104. The first interworking unit 202 maps ATMcells to broadband frames, such as SONET frames. In addition, the firstinterworking unit 202 also maps broadband frames, such as SONET frames,to ATM cells. The first interworking unit 202 converts the ATM cells toTDM formatted user communications. In some instances, the firstinterworking unit 202 may transport control messages which may includedata to the signaling processor 104.

In some embodiments, the first interworking unit 202 is operational toimplement digital signal processing as instructed in the controlmessages. An example of digital signal processing is echo cancellationor continuity testing. A preferred embodiment of the first interworkingunit 202 is discussed in detail below.

The first cross connect 204 is any device, such as an ATM cross connect,that provisions virtual connections over broadband paths, such as ATMconnections over SONET paths in a SONET ring. The first cross connect204 provides a plurality of ATM virtual connections between the firstADM 206 and the first interworking unit 202. In ATM, virtual connectionsare designated by the VPI/VCI in the cell header. The first crossconnect 204 is configured to accept ATM cells from, and transport ATMcells to, the first interworking unit 202 and to provide a plurality ofVPI/VCI connections to the first ADM 206.

The VCIs are used to differentiate individual calls on the VPI betweenthe first cross connect 204 and the first ADM 206 and to identify thedestination or handling point of the call. For example, VPI/VCI "A" maybe provisioned from the first interworking unit 202, through the firstcross connect 204, through the first ADM 206, and "destined" for aninterworking unit connected to a cross connect in the second broadbandinterface 108 that is associated with the second communication device146. VPI/VCI "B" may be provisioned from the first interworking unit202, through the first cross connect 204, through the first ADM 206, and"destined" for an interworking unit connected to a cross connect in thefourth broadband interface 112 that is associated with the ILEC 154.(See FIG. 1.) An example of an ATM cross connect is the NEC Model 20.

The first cross connect 204 provisions the connections from the firstinterworking unit 202, through the first ADM 206, and to another crossconnect and from another cross connect, through the first ADM, and tothe first interworking unit. In a SONET system, the first cross connect204 receives SONET frames containing mapped ATM cells from the first ADM206 and cross connects the SONET frames on the connection to the firstinterworking unit 202. In addition, in a SONET system, the first crossconnect 204 receives SONET frames containing mapped ATM cells from thefirst interworking unit 202 and cross connects the SONET frames on thedesignated VPI/VCI virtual connection to the first ADM 206.

The first ADM 206 adds traffic to the broadband paths of the broadbandring for the connections 118 and 128 or drops traffic from the broadbandpaths for the connections. The first ADM 206 may add or drop trafficthat is transported at levels extending from the DS1 level to the OClevel or the STS level and to equivalent standards. The broadband pathsfor connections leading to and from the first ADM 206, such as theconnections 118 and 128, are provisioned by the first ADM 206 as, forexample, SONET paths to all other communication devices in the broadbandsystem 102. Thus, for example, a SONET path is provisioned between thefirst ADM 206 in the first broadband interface 106 and an ADM in thesecond broadband interface 108 to carry traffic for the virtualconnection for the connection 118. Another SONET path is provisionedbetween the first ADM 206 in the first broadband interface 106 and anADM in the sixth broadband interface 116 to carry traffic for thevirtual connection for the connection 128. (See FIG. 1.)

Referring still to FIG. 2, the second broadband interface 108 iscomprised of a second interworking unit 212, a second cross connect 214,and a second ring terminal, such as a second add/drop multiplexer (ADM)216. The second cross connect 214 is connected to the secondinterworking unit 212 through a connection 218 and to the second ADM 206through a connection 220.

The second interworking unit 212 interworks traffic between variousprotocols. Preferably, the second interworking unit 212 interworksbetween ATM traffic and non-ATM traffic. The second interworking unit212 operates in accordance with control messages received from thesignaling processor 104 over the link 132. These control messages aretypically provided on a call-by-call basis and typically identify anassignment between a DS0 and a VPI/VCI for which user communications areinterworked.

Thus, the second interworking unit 212 converts TDM formatted usercommunications to ATM cells that identify virtual connections selectedby the signaling processor 104. The second interworking unit 212 mapsATM cells to broadband frames, such as SONET frames. In addition, thesecond interworking unit 212 also maps broadband frames, such as SONETframes, to ATM cells. The second interworking unit 212 converts ATMcells to TDM formatted user communications. In some instances, thesecond interworking unit 212 may transport control messages which mayinclude data to the signaling processor 104.

In some embodiments, the second interworking unit 212 is operational toimplement digital signal processing as instructed in the controlmessages. An example of digital signal processing is echo cancellationor continuity testing. A preferred embodiment of the second interworkingunit 212 is discussed in detail below.

The second cross connect 214 is any device, such as an ATM crossconnect, that provisions virtual connections over broadband paths, suchas ATM connections over a SONET ring. The second cross connect 214provides a plurality of ATM virtual connections between the second ADM216 and the second interworking unit 212. In ATM, virtual connectionsare designated by the VPI/VCI in the cell header. The second crossconnect 214 is configured to accept ATM cells from, and transport ATMcells to, the second interworking unit 212 and to provide a plurality ofVPI/VCI connections to the second ADM 216.

The VCIs are used to differentiate individual calls on the VPI betweenthe second ADM 216 and the second interworking unit 212 and to identifythe destination or handling point of the call. For example, VPI/VCI "A"may be provisioned from the second interworking unit 212, through thesecond cross connect 214, through the second ADM 216, and "destined" foran interworking unit connected to a cross connect in the first broadbandinterface 106 that is associated with the first communication device142. VPI/VCI "B" may be provisioned from the second interworking unit212, through the second cross connect 214, through the second ADM 216,and "destined" for an interworking unit connected to a cross connect inthe fourth broadband interface 112 that is associated with the ILEC 154.(See FIG. 1.) An example of an ATM cross connect is the NEC Model 20.

The second cross connect 214 provisions the virtual connections from thesecond interworking unit 212, through the second ADM 216, and to othercross connects and from other cross connects, through the the ADM, andto the second interworking unit. In a SONET system, the second crossconnect 214 receives SONET frames containing mapped ATM cells from thesecond ADM 216 and cross connects the SONET frames on the connection tothe second interworking unit 212. In addition, in a SONET system, thesecond cross connect 214 receives SONET frames containing mapped ATMcells from the second interworking unit 212 and cross connects the SONETframes on the designated virtual connection for the connection to thesecond ADM 216.

The second ADM 216 adds traffic to the broadband paths of the broadbandring for the connections 118 and 120 or drops traffic from the broadbandpaths for the connections. The second ADM 216 may add or drop trafficthat is transported at levels extending from the DS1 level to the OClevel or the STS level and equivalent standards. The broadband paths forconnections leading to and from the second ADM 216, such as theconnections 118 and 120, are provisioned by the second ADM 216 as, forexample, SONET paths to all other communication devices in the broadbandsystem 102. Thus, for example, a SONET path is provisioned between thesecond ADM 216 in the second broadband interface 108 and the first ADM206 in the first broadband interface 106 to carry traffic for thevirtual connection for the connection 118. Another SONET path isprovisioned between the second ADM 216 in the second broadband interface108 and an ADM in the sixth broadband interface 116 to carry traffic forthe virtual connection for the connection 120. (See FIG. 1.)

A broadband path in a SONET system is identified by a SONET OC level orSTS level path. Similarly, a virtual connection is identified by an ATMVPI/VCI or companion ATM VPIs/VCIs. This combination of the provisionedvirtual connection in the provisioned broadband path shall be referredto herein as the ATM connection over the SONET path or as the virtualconnection of the broadband path. Thus, for example, the provisionedVPI/VCI between the first interworking unit 202 and the secondinterworking unit 212, through the first cross connect 204 and thesecond cross connect 214, which extends through the provisionedbroadband path of the SONET ring between the first ADM 206 and thesecond ADM 216 is referred to herein as the virtual connection over thebroadband path for the connection 118 or as the ATM connection of theSONET ring for the connection 118.

It will be appreciated that the system described above may be modifiedto incorporate various other carrier network and system equipment. Forexample, in some cases, a terminal multiplexer or an access multiplexermay be used instead of the add/drop multiplexer of the preferred systemdescribed above.

The first broadband interface 106 and the second broadband interface 108of FIG. 2 operate as follows when the first communication device 142transports a call to the second communication device 146 in a SONETbroadband system 102. The operation of the first broadband interface 106and the second broadband interface 108 are representative of the otherbroadband interfaces 110, 112, 114, and 116.

Referring to FIG. 1, it will be understood that SONET paths areprovisioned from each broadband interface 106, 108, 110, 112, 114, and116 to every other broadband interface in the broadband network 102. Forexample, the fifth broadband interface 114 will have a SONET pathprovisioned to every other broadband interface 106, 108, 110, 112, and116. It will be appreciated that this forms a flat architecture betweenthe broadband interfaces 106, 108, 110, 112, 114, and 116 which isimplemented over the SONET ring.

Referring to FIG. 1 and FIG. 2, the SONET paths are provisioned betweenthe ADMs in each broadband interface 106, 108, 110, 112, 114, and 116,such as between the first ADM 206 and the second ADM 216. In a similarfashion, ATM connections are provisioned between the cross connects ofeach broadband interface 106, 108, 110, 112, 114, and 116 to the crossconnects in each other broadband interface and to the associatedinterworking units. For example, the first cross connect 204 in thefirst broadband interface 106 uses the SONET paths provided by the ADM206 to provision an ATM connection from the first interworking unit 202through the second cross connect 214 in the second broadband interface108 to the second interworking unit 212.

The interworking units of each of the broadband interfaces 106, 108,110, 112, 114, and 116 have a provisioned ATM connection over the SONETring to each of the interworking units in the other broadbandinterfaces. Thus, it can be seen that the first interworking unit 202 inthe first broadband interface 106 has a provisioned ATM connection overthe SONET ring to each of the interworking units in the other broadbandinterfaces 108, 110, 112, 114, and 116. For example, the firstinterworking unit 202 in the first broadband interface 106 has aprovisioned ATM connection over the SONET ring to the secondinterworking unit 212 in the second broadband interface 108. Because theATM connections are provisioned over the SONET ring, when the signalingprocessor 104 selects a connection, an interworking unit places the ATMcells on the selected connection, and the ATM cells are transported inthe broadband frames to the receiving interworking unit. It will beappreciated that ATM connections may be provisioned over the SONET ringprior to a call, and that ATM connections may be reprovisioned over theSONET ring during or after a call.

When a call is transported, it must conform to both the ATM protocol andthe SONET protocol. The user communications are first placed into ATMcells that identify the VPI/VCI of the selected connection. This allowsATM capable communication devices to transport calls to, and receivecalls from, other ATM capable communication devices. The ATM cells arethen mapped into SONET frames to be transported and received over theSONET paths. Typically, the ATM cells are mapped to an OC-3 level or anSTS-3c level communication. It should be noted that, for clarity, ATMcells that are mapped to SONET frames may be referred to below as ATMcells, without the reference to the SONET frame mapping. One skilled inthe art will appreciate that ATM cells are mapped to and from SONETframes at the first and second interworking units 202 and 212.

When a call is to be connected, the first communication device 142transports the call signaling to the signaling processor 104 over thelink 166 in an appropriate format, such as SS7. The first communicationdevice 142 transports the user communications to the first interworkingunit 202 over the connection 144 in a communication format, such as aTDM format over a DS0 embedded in a DS3.

The signaling processor 104 receives the call signaling and processesthe call signaling to determine connections for the call. The signalingprocessor 104 selects a first connection 118 over which the ATMformatted user communications will be transported from the firstbroadband interface 106. The selected first connection 118 is an ATMconnection over a SONET path, such as a VPI/VCI in an OC-48 pipe. Thesignaling processor 104 transports a control message over the link 130to the first interworking unit 202. The control message identifies theselected first connection 118.

The signaling processor 104 also processes the call signaling todetermine a second connection 148 for the call over which the secondinterworking unit 212 will transport TDM formatted user communicationsto the second communication device 146. The selected second connection148 is a TDM connection, such as a DS0 embedded in a DS3. The signalingprocessor 104 transports a control message over the link 132 to thesecond interworking unit 212. The control message identifies theselected second connection 148.

The first interworking unit 202 receives the control message from thesignaling processor 104 and the user communications from the firstcommunication device 142. The first interworking unit 202 interworks theTDM formatted user communications to ATM cells that identify theselected VPI/VCI of the first connection 118..

The ATM cells are mapped to SONET frames for the requisite OC level orSTS level communication. The first interworking unit 202 then transportsthe ATM cells in the SONET frames to the first cross connect 204 over aconnection 208. Preferably, the connection is an OC-3.

The first cross connect 204 receives the SONET frames containing the ATMcells. The first cross connect 204 removes the ATM cells from the SONETframes and cross connects the ATM cells through the ATM fabric to theappropriate provisioned virtual connection for the selected firstconnection 118. The first cross connect 204 maps the ATM cells back intoSONET frames at the output of the first cross connect. The SONET framescontaining the ATM cells are transported to the first ADM 206 over aprovisioned path in the connection 210 for the VPI/VCI of the selectedfirst connection 118. The connection 210 preferably is an OC level or anSTS level connection, such as an OC-3. It can be seen that cells aretransported to the correct connection when the correct VPI/VCI isselected.

The first ADM 206 receives the SONET frames containing the ATM cellsfrom the first cross connect 204 over the connection 210. The first ADM206 adds the frames on the provisioned broadband path on the SONET ringthat has the corresponding provisioned VPI/VCI of the selected firstconnection 118. The SONET frames are transported over the SONET ring on,for example, an OC-48 to the second broadband interface 108.

The second ADM 216 receives the SONET frames containing the ATM cellsover the selected first connection 118 of the SONET ring. The second ADM216 drops the SONET frames containing the ATM cells from the SONET ringto the second cross connect 214.

The second cross connect 214 receives the SONET frames over theconnection 220. The second cross connect 214 cross connects the SONETframes containing the ATM cells to the second interworking unit 212 overthe provisioned path in the connection 218 that corresponds to theVPI/VCI in the ATM cells.

The second interworking unit 212 receives the SONET frames from thesecond cross connect 214 and the control message from the signalingprocessor 104. The second interworking unit 212 maps the SONET frames tothe ATM cells. The second interworking unit 212 converts the ATM cellsto TDM formatted user communications and transports the TDM formatteduser communications to the second communication device 146 over theselected second connection 148.

Referring still to FIG. 2, a call may be connected from the secondcommunication device 146 to the first communication device 142. Theprocess for the connection and the transport of the user communicationsis the same as described above, except that the second broadbandinterface 108 transports the user communications as ATM cells mapped inSONET frames and the first broadband interface 106 receives the usercommunications as ATM cells mapped in the SONET frames.

Although the system is described above using SONET designations, theinvention is equally applicable for use with SDH systems. For example,ATM cells may be mapped to STM-1 electrical/optical (E/O) frames in theSDH system instead of analogous STS-3c/OC-3 frames in a SONET system.Likewise, ATM cells and lower SDH level communications may bemultiplexed or mapped up to STM-12 E/O communications in the SDH systeminstead of analogous STS-48/OC-48 communications in a SONET system.

Referring to FIGS. 1 and 2, it will be appreciated that the functions ofthe signaling processor 104, the first interworking unit 202, the firstcross connect 204, and the first ADM 206 provide switching-typefunctions for ATM traffic being transported to communication devices inthe SONET ring from the first broadband interface 106. Moreover, thefunctions of the signaling processor 104, the second interworking unit212, the second cross connect 214, and the second ADM 216 provideswitching-type functions for traffic being transported to communicationdevices, such as switches, from the SONET ring.

These switching functions give the broadband system 102 the ability toconnect and switch calls to any location in the broadband system 102.This allows the broadband system to complete such functions as localnumber portability so that a telephone service customer can switchservices from, for example, the ILEC 154 to the CLEC 158 and keep thesame local telephone number. Other services, including intelligentnetwork services, also may be provided.

The present invention as explained above may be adapted for use withother devices or with fewer devices. For example, the first broadbandinterface 106 may be adapted to be used without the cross connect 204.However, some switching functionality may be eliminated becausebroadband paths then would be provisioned to the first interworking unit202, and the first interworking unit would have to select the broadbandpath. Multiple SONET paths may be provisioned from the firstinterworking unit 202 to each call destination.

As illustrated in FIG. 3, the broadband interface 302 may have multipleinterworking units or cross connects. Thus, a cross connect 304 may beconnected to a first interworking unit 306 and to a second interworkingunit 308, in addition to an ADM 310. A signaling processor 312 processescall signaling and determines connections and processing for thecomponents of the broadband interface 302. The first and secondinterworking units 306 and 308 may be in the same proximate location orin different proximate locations. Moreover, the cross connect 304 orother components may be connected to another cross connect or to agateway (not shown).

As illustrated in FIG. 4, the broadband system 102B may use an STP 404.In addition, the broadband system 102B may be configured so that aplurality of broadband interfaces are each connected to its ownsignaling processor. In this configuration, the broadband system 102Bhas a first broadband interface 404 linked to a first signalingprocessor 406, a second broadband interface 408 linked to a secondsignaling processor 410, a third broadband interface 412 linked to athird signaling processor 414, a fourth broadband interface 416 linkedto a fourth signaling processor 418, a fifth broadband interface 420linked to a fifth signaling processor 422, and a sixth broadbandinterface 424 linked to a sixth signaling processor 426. Each of thesignaling processors 406, 410, 414, 418, 422, and 426 are linked to theSTP 402. For clarity, the links and the connections are not referenced.

In addition, it will be appreciated that the system of the presentinvention may connect calls for a variety of communication devices. Forexample, a broadband interface may be connected to a class 4 switch, aclass 5 switch, or a class 4/5 switch. These switches may, in turn, beconnected to other class 4, class 5, or class 4/5 switches. Thebroadband system and broadband interfaces may be used to connect andprocess calls in a local architecture or in an interexchangearchitecture. In addition, the broadband system and broadband interfacesmay be used to connect and process calls in facility based andnon-facility based traffic. Moreover, the broadband interfaces mayconnect to in-band signaling communication devices as well as theout-of-band signaling communication devices.

The ATM Interworking Unit

FIG. 5 shows one embodiment of an interworking unit which is an ATMinterworking unit 502 suitable for the present invention for use with aSONET system, but other interworking units that support the requirementsof the invention are also applicable. The ATM interworking unit 502 mayreceive and transmit in-band and out-of-band calls.

The ATM interworking unit 502 has a control interface 504, an OC-N/STS-Ninterface 506, a DS3 interface 508, a DS1 interface 510, a DS0 interface512, a signal processor 514, an ATM adaptation layer (AAL) 516, anOC-M/STS-M interface 518, and an ISDN/GR-303 interface 520. As usedherein in conjunction with OC or STS, "N" refers to an integer, and "M"refers to an integer.

The control interface 502 accepts control messages from the signalingprocessor 522. In particular, the control interface 504 identifies DS0connections and virtual connection assignments in the control messagesfrom the signaling processor 522. These assignments are provided to theAAL 516 for implementation.

The OC-N/STS-N interface 506, the DS3 interface 508, the DS1 interface510, the DS0 interface 512, and the ISDN/GR-303 interface 520 each canaccept calls, including user communications, from a communication device524. Likewise, the OC-M/STS-M interface 518 can accept calls, includinguser communications, from a communication device 526.

The OC-N/STS-N interface 506 accepts OC-N formatted calls and STS-Nformatted calls and converts the calls from the OC-N or STS-N formats tothe DS3 format. The DS3 interface 508 accepts calls in the DS3 formatand converts the calls to the DS1 format. The DS3 interface 508 canaccept DS3s from the OC-N/STS-N interface 506 or from an externalconnection. The DS1 interface 510 accepts the calls in the DS1 formatand converts the calls to the DS0 format. The DS1 interface 510 canaccept DS1s from the DS3 interface 508 or from an external connection.The DS0 interface 512 accepts calls in the DS0 format and provides aninterface to the AAL 516. The ISDN/GR-303 interface 520 accepts calls ineither the ISDN format or the GR-303 format and converts the calls tothe DS0 format. In addition, each interface may transmit signals in likemanner to the communication device 524.

The OC-M/STS-M interface 518 is operational to accept ATM cells from theAAL 516 and to transmit the ATM cells over the connection to thecommunication device 526. The OC-M/STS-M interface 518 may also acceptATM cells in the OC or STS format and transmit them to the AAL 516.

The AAL 516 comprises both a convergence sublayer and a segmentation andreassembly (SAR) sublayer. The AAL 516 is operational to acceptcommunication device information in the DS0 format from the DS0interface 512 and to convert the communication device information intoATM cells. AALs are known in the art and information about AALs isprovided by International Telecommunications Union (ITU) document I.363,which is incorporated fully herein by reference. An AAL for voice callsis described in U.S. patent application Ser. No. 08/395,745, which wasfiled on Feb. 28, 1995, and entitled "Cell Processing for VoiceTransmission," and which is incorporated herein by reference.

The AAL 516 obtains from the control interface 504 the virtual pathidentifier (VPI) and the virtual channel identifier (VCI) for each DS0for each call connection. The AAL 516 also obtains the identity of theDS0 for each call (or the DS0s for an N×64 call). The AAL 516 thentransfers the communication device information between the identifiedDS0 and the identified ATM virtual connection. An acknowledgment thatthe assignments have been implemented may be sent to the signalingprocessor 522 if desired. Calls with multiple 64 Kilo-bits per second(Kbps) DS0s are known as N×64 calls. If desired, the AAL 516 can beconfigured to accept control messages through the control interface 504for N×64 calls.

As discussed above, the ATM interworking unit 502 also handles calls inthe opposite direction, that is, in the direction from the OC-M/STS-Minterface 518 to the DS0 interface 512, including calls exiting from theDS1 interface 510, the DS3 interface 508, the OC-N/STS-N interface 506,and the ISDN/GR-303 interface 520. For this traffic, the VPI/VCI hasbeen selected already and the traffic has been routed through thecross-connect (not shown). As a result, the AAL 516 only needs toidentify the pre-assigned DS0 for the selected VPI/VCI. This can beaccomplished through a look-up table. In alternative embodiments, thesignaling processor 522 can provide this DS0-VPI/VCI assignment throughthe control interface 504 to the AAL 516.

A technique for processing VPI/VCIs is disclosed in U.S. patentapplication Ser. No. 08/653,852, which was filed on May 28, 1996, andentitled "Telecommunications System with a Connection ProcessingSystem," and which is incorporated herein by reference.

DS0 connections are bi-directional and ATM connections are typicallyuni-directional. As a result, two virtual connections in opposingdirections typically will be required for each DS0. Those skilled in theart will appreciate how this can be accomplished in the context of theinvention. For example, the cross-connect can be provisioned with asecond set of VPI/VCIs in the opposite direction as the original set ofVPI/VCIs. For each call, ATM interworking multiplexers would beconfigured to invoke automatically this second VPI/VCI to provide abi-directional virtual connection to match the bi-directional DS0 on thecall.

In some embodiments, it may be desirable to incorporate digital signalprocessing capabilities at the DS0 level. It may also be desired toapply echo cancellation to selected DS0 circuits. In these embodiments,a signal processor 514 would be included either separately (as shown) oras a part of the DS0 interface 512. The signaling processor 522 would beconfigured to send control messages to the ATM interworking unit 502 toimplement particular features on particular DS0 circuits. Alternatively,lookup tables may be used to implement particular features forparticular circuits or VPIs/VCIs.

FIG. 6 shows another embodiment of an interworking unit which is an ATMinterworking unit 602 suitable for the present invention. The ATMinterworking unit 502 may receive and transmit in-band and out-of-bandcalls.

The ATM interworking unit 602 is for use with an SDH system and has acontrol interface 604, an STM-N electrical/optical (E/O) interface 606,an E3 interface 608, an E1 interface 610, an E0 interface 612, a signalprocessor 614, an ATM adaptation layer (AAL) 616, an STM-Melectrical/optical (E/O) interface 618, and a digital private networksignaling system (DPNSS) interface 620. As used herein in conjunctionwith STM, "N" refers to an integer, and "M" refers to an integer.

The control interface 604 accepts control messages from the signalingprocessor 622. In particular, the control interface 604 identifies E0connections and virtual connection assignments in the control messagesfrom the signaling processor 622. These assignments are provided to theAAL 616 for implementation.

The STM-N E/O interface 606, the E3 interface 608, the E1 interface 610,the E0 interface 612, and the DPNSS interface 620 each can accept calls,including user communications, from a second communication device 624.Likewise, the STM-M E/O interface 618 can accept calls, including usercommunications, from a third communication device 626.

The STM-N E/O interface 606 accepts STM-N electrical or opticalformatted calls and converts the calls from the STM-N electrical orSTM-N optical format to the E3 format. The E3 interface 608 acceptscalls in the E3 format and converts the calls to the E1 format. The E3interface 608 can accept E3s from the STM-N E/O interface 606 or from anexternal connection. The E1 interface 610 accepts the calls in the E1format and converts the calls to the E0 format. The E1 interface 610 canaccept E1s from the STM-N E/O interface 606 or the E3 interface 608 orfrom an external connection. The E0 interface 612 accepts calls in theE0 format and provides an interface to the AAL 616. The DPNSS interface620 accepts calls in the DPNSS format and converts the calls to the E0format. In addition, each interface may transmit signals in a likemanner to the communication device 624.

The STM-M E/O interface 618 is operational to accept ATM cells from theAAL 616 and to transmit the ATM cells over the connection to thecommunication device 626. The STM-M E/O interface 618 may also acceptATM cells in the STM-M E/O format and transmit them to the AAL 616.

The AAL 616 comprises both a convergence sublayer and a segmentation andreassembly (SAR) sublayer. The AAL 616 is operational to acceptcommunication device information in the E0 format from the E0 interface612 and to convert the communication device information into ATM cells.

The AAL 616 obtains from the control interface 604 the virtual pathidentifier and the virtual channel identifier for each call connection.The AAL 616 also obtains the identity of each call. The AAL 616 thentransfers the communication device information between the identified E0and the identified ATM virtual connection. An acknowledgment that theassignments have been implemented may be sent back to the signalingprocessor 622 if desired. If desired, the AAL 616 can be configured toaccept control messages through the control interface 604 for N×64calls.

As discussed above, the ATM interworking unit 602 also handles calls inthe opposite direction, that is, in the direction from the STM-M E/Ointerface 618 to the E0 interface 612, including calls exiting from theE1 interface 610, the E3 interface 608, the STM-N E/O interface 606, andthe DPNSS interface 620. For this traffic, the VPI/VCI has been selectedalready and the traffic has been routed through the cross-connect (notshown). As a result, the AAL 616 only needs to identify the pre-assignedE0 for the selected VPI/VCI. This can be accomplished through a look-uptable. In alternative embodiments, the signaling processor 622 canprovide this VPI/VCI assignment through the control interface 604 to theAAL 616.

E0 connections are bi-directional and ATM connections typically areuni-directional. As a result, two virtual connections in opposingdirections typically will be required for each E0. Those skilled in theart will appreciate how this can be accomplished in the context of theinvention. For example, the cross-connect can be provisioned with asecond set of VPI/VCIs in the opposite direction as the original set ofVPI/VCIs. For each call, ATM interworking multiplexers would beconfigured to automatically invoke this second VPI/VCI to provide abi-directional virtual connection to match the bi-directional E0 on thecall.

In some instances, it may be desirable to incorporate digital signalprocessing capabilities at the E0 level. Also, it may be desirable applyecho cancellation. In these embodiments, a signal processor 614 would beincluded either separately (as shown) or as a part of the E0 interface612. The signaling processor 622 would be configured to send controlmessages to the ATM interworking unit 602 to implement particularfeatures on particular circuits. Alternatively, lookup tables may beused to implement particular features for particular circuits orVPIs/VCIs.

The Signaling Processor

The signaling processor is referred to as a call/connection manager(CCM), and it receives and processes telecommunications call signalingand control messages to select connections that establish communicationpaths for calls. In the preferred embodiment, the CCM processes ISDN,GR-303, and SS7 signaling to select connections for a call. CCMprocessing is described in a U.S. patent application having attorneydocket number 1148, which is entitled "Telecommunication System," whichis assigned to the same assignee as this patent application, and whichis incorporated herein by reference.

In addition to selecting connections, the CCM performs many otherfunctions in the context of call processing. It not only can controlrouting and select the actual connections, but it also can validatecallers, control echo cancelers, generate billing information, invokeintelligent network functions, access remote databases, manage traffic,and balance network loads. One skilled in the art will appreciate howthe CCM described below can be adapted to operate in the aboveembodiments.

FIG. 7 depicts a version of the CCM. Other versions also arecontemplated. In the embodiment of FIG. 7, the CCM 702 controls an ATMinterworking unit, such as an ATM interworking multiplexer (mux) thatperforms interworking of DS0s and VPI/VCIs. However, the CCM may controlother communications devices and connections in other embodiments.

The CCM 702 comprises a signaling platform 704, a control platform 706,and an application platform 708. Each of the platforms 704, 706, and 708is coupled to the other platforms.

The signaling platform 704 is externally coupled to the signalingsystems--in particular to SS7 signaling systems having a messagetransfer part (MTP), an ISDN user part (ISUP), a signaling connectioncontrol part (SCCP), an intelligent network application part (INAP), anda transaction capabilities application part (TCAP). The control platform706 is externally coupled to an interworking unit control, an echocontrol, a resource control, billing, and operations.

The signaling platform 704 preferably is an SS7 platform that comprisesMTP levels 1-3, ISUP, TCAP, SCCP, and INAP functionality and isoperational to transmit and receive the SS7 messages. The ISUP, SCCP,INAP, and TCAP functionality use MTP to transmit and receive the SS7messages. Together, this functionality is referred as an "SS7 stack,"and it is well known. The software required by one skilled in the art toconfigure an SS7 stack is commercially available, for example, from theTrillium company.

The control platform 706 is comprised of various external interfacesincluding an interworking unit interface, an echo interface, a resourcecontrol interface, a billing interface, and an operations interface. Theinterworking unit interface exchanges messages with at least oneinterworking unit. These messages comprise DS0 to VPI/VCI assignments,acknowledgments, and status information. The echo control interfaceexchanges messages with echo control systems. Messages exchanged withecho control systems might include instructions to enable or disableecho cancellation on particular DS0s, acknowledgments, and statusinformation.

The resource control interface exchanges messages with externalresources. Examples of such resources are devices that implementcontinuity testing, encryption, compression, tonedetection/transmission, voice detection, and voice messaging. Themessages exchanged with resources are instructions to apply the resourceto particular DS0s, acknowledgments, and status information. Forexample, a message may instruct a continuity testing resource to providea loopback or to send and detect a tone for a continuity test.

The billing interface transfers pertinent billing information to abilling system. Typical billing information includes the parties to thecall, time points for the call, and any special features applied to thecall. The operations interface allows for the configuration and controlof the CCM 702. One skilled in the art will appreciate how to producethe software for the interfaces in the control platform 706.

The application platform 708 is functional to process signalinginformation from the signaling platform 704 in order to selectconnections. The identity of the selected connections are provided tothe control platform 706 for the interworking unit interface. Theapplication platform 708 is responsible for validation, translation,routing, call control, exceptions, screening, and error handling. Inaddition to providing the control requirements for the interworkingunit, the application platform 708 also provides requirements for echocontrol and resource control to the appropriate interface of the controlplatform 706. In addition, the application platform 708 generatessignaling information for transmission by the signaling platform 704.The signaling information might be ISUP, INAP, or TCAP messages toexternal network elements. Pertinent information for each call is storedin a call control block (CCB) for the call. The CCB can be used fortracking and billing the call.

The application platform 708 operates in general accord with the BasicCall Model (BCM) defined by the ITU. An instance of the BCM is createdto handle each call. The BCM includes an originating process and aterminating process. The application platform 708 includes a serviceswitching function (SSF) that is used to invoke the service controlfunction (SCF). Typically, the SCF is contained in a service controlpoint (SCP). The SCF is queried with TCAP or INAP messages. Theoriginating or terminating processes will access remote databases withintelligent network (IN) functionality via the SSF function.

Software requirements for the application platform 708 can be producedin specification and description language (SDL) defined in ITU-T Z.100.The SDL can be converted into C code. Additional C and C++ code can beadded as required to establish the environment.

The CCM 702 can be comprised of the above-described software loaded ontoa computer. The computer can be an Integrated Micro Products (IMP)FT-Sparc 600 using the Solaris operating system and conventionaldatabase systems. It may be desirable to utilize the multi-threadingcapability of a Unix operating system.

From FIG. 7, it can be seen that the application platform 708 processessignaling information to control numerous systems and facilitate callconnections and services. The SS7 signaling is exchanged with externalcomponents through the signaling platform 704, and control informationis exchanged with external systems through the control platform 706.Advantageously, the CCM 702 is not integrated into a switch centralprocessing unit (CPU) that is coupled to a switching matrix. Unlike anSCP, the CCM 702 is capable of processing ISUP messages independently ofTCAP queries.

SS7 Message Designations

SS7 messages are well known. Designations for various SS7 messagescommonly are used. Those skilled in the art are familiar with thefollowing message designations:

    ______________________________________                                        ACM        Address Complete Message                                           ANM        Answer Message                                                     BLO        Blocking                                                           BLA        Blocking Acknowledgment                                            CPG        Call Progress                                                      CRG        Charge Information                                                 CGB        Circuit Group Blocking                                             CGBA       Circuit Group Blocking Acknowledgment                              GRS        Circuit Group Reset                                                GRA        Circuit Group Reset Acknowledgment                                 CGU        Circuit Group Unblocking                                           CGUA       Circuit Group Unblocking Acknowledgment                            CQM        Circuit Group Query                                                CQR        Circuit Group Query Response                                       CRM        Circuit Reservation Message                                        CRA        Circuit Reservation Acknowledgment                                 CVT        Circuit Validation Test                                            CVR        Circuit Validation Response                                        CFN        Confusion                                                          COT        Continuity                                                         CCR        Continuity Check Request                                           EXM        Exit Message                                                       INF        Information                                                        INR        Information Request                                                IAM        Initial Address                                                    LPA        Loop Back Acknowledgment                                           PAM        Pass Along                                                         REL        Release                                                            RLC        Release Complete                                                   RSC        Reset Circuit                                                      RES        Resume                                                             SUS        Suspend                                                            UBL        Unblocking                                                         UBA        Unblocking Acknowledgment                                          UCIC       Unequipped Circuit Identification Code.                            ______________________________________                                    

CCM Tables

Call processing typically entails two aspects. First, an incoming or"originating" connection is recognized by an originating call process.For example, the initial connection that a call uses to enter a networkis the originating connection in that network. Second, an outgoing or"terminating" connection is selected by a terminating call process. Forexample, the terminating connection is coupled to the originatingconnection in order to extend the call through the network. These twoaspects of call processing are referred to as the originating side ofthe call and the terminating side of the call.

FIG. 8 depicts a data structure used by the application platform 708 toexecute the BCM. This is accomplished through a series of tables thatpoint to one another in various ways. The pointers are typicallycomprised of next function and next index designations. The nextfunction points to the next table, and the next index points to an entryor a range of entries in that table. The data structure has a trunkcircuit table 802, a trunk group table 804, an exception table 806, anANI table 808, a called number table 810, and a routing table 812.

The trunk circuit table 802 contains information related to theconnections. Typically, the connections are DS0 or ATM connections.Initially, the trunk circuit table 802 is used to retrieve informationabout the originating connection. Later, the table is used to retrieveinformation about the terminating connection. When the originatingconnection is being processed, the trunk group number in the trunkcircuit table 802 points to the applicable trunk group for theoriginating connection in the trunk group table 804.

The trunk group table 804 contains information related to theoriginating and terminating trunk groups. When the originatingconnection is being processed, the trunk group table 804 providesinformation relevant to the trunk group for the originating connectionand typically points to the exception table 806.

The exception table 806 is used to identify various exception conditionsrelated to the call that may influence the routing or other handling ofthe call. Typically, the exception table 806 points to the ANI table808. Although, the exception table 806 may point directly to the trunkgroup table 804, the called number table 810, or the routing table 812.

The ANI table 808 is used to identify any special characteristicsrelated to the caller's number. The caller's number is commonly known asautomatic number identification (ANI). The ANI table 808 typicallypoints to the called number table 810. Although, the ANI table 808 maypoint directly to the trunk group table 804 or the routing table 812.

The called number table 810 is used to identify routing requirementsbased on the called number. This will be the case for standard telephonecalls. The called number table 810 typically points to the routing table812. Although, it may point to the trunk group table 804.

The routing table 812 has information relating to the routing of thecall for the various connections. The routing table 812 is entered froma pointer in the exception table 806, the ANI table 808, or the callednumber table 810. The routing table 812 typically points to a trunkgroup in the trunk group table 804.

When the exception table 806, the ANI table 808, the called number table810, or the routing table 812 point to the trunk group table 804, theyeffectively select the terminating trunk group. When the terminatingconnection is being processed, the trunk group number in the trunk grouptable 804 points to the trunk group that contains the applicableterminating connection in the trunk circuit table 804.

The terminating trunk circuit is used to extend the call. The trunkcircuit is typically a VPI/VCI or a DS0. Thus, it can be seen that bymigrating through the tables, a terminating connection can be selectedfor a call.

FIG. 9 is an overlay of FIG. 8. The tables from FIG. 8 are present, butfor clarity, their pointers have been omitted. FIG. 9 illustratesadditional tables that can be accessed from the tables of FIG. 8. Theseinclude a CCM ID table 902, a treatment table 904, a query/responsetable 906, and a message table 908.

The CCM ID table 902 contains various CCM SS7 point codes. It can beaccessed from the trunk group table 804, and it points back to the trunkgroup table 804.

The treatment table 904 identifies various special actions to be takenin the course of call processing. This will typically result in thetransmission of a release message (REL) and a cause value. The treatmenttable 904 can be accessed from the trunk circuit table 802, the trunkgroup table 804, the exception table 806, the ANI table 808, the callednumber table 810, the routing table 812, and the query/response table906.

The query/response table 906 has information used to invoke the SCF. Itcan be accessed by the trunk group table 804, the exception table 806,the ANI table 808, the called number table 810, and the routing table812. It points to the trunk group table 804, the exception table 806,the ANI table 808, the called number table 810, the routing table 812,and the treatment table 904.

The message table 908 is used to provide instructions for messages fromthe termination side of the call. It can be accessed by the trunk grouptable 804 and points to the trunk group table 804.

FIGS. 14-21 depict examples of the various tables described above. FIG.10 depicts an example of the trunk circuit table. Initially, the trunkcircuit table is used to access information about the originatingcircuit. Later in the processing, it is used to provide informationabout the terminating circuit. For originating circuit processing, theassociated point code is used to enter the table. This is the point codeof the switch or CCM associated with the originating circuit. Forterminating circuit processing, the trunk group number is used to enterthe table.

The table also contains the circuit identification code (CIC). The CICidentifies the circuit which is typically a DS0 or a VPI/VCI. Thus, theinvention is capable of mapping the SS7 CICs to the ATM VPI/VCI. If thecircuit is ATM, the virtual path (VP) and the virtual channel (VC) alsocan be used for identification. The group member number is a numericcode that is used for terminating circuit selection. The hardwareidentifier identifies the location of the hardware associated with theoriginating circuit. The echo canceler (EC) identification (ID) entryidentifies the echo canceler for the originating circuit.

The remaining fields are dynamic in that they are filled during callprocessing. The echo control entry is filled based on three fields insignaling messages: the echo suppresser indicator in the IAM or CRM, theecho control device indicator in the ACM or CPM, and the informationtransfer capability in the IAM. This information is used to determine ifecho control is required on the call. The satellite indicator is filledwith the satellite indicator in the IAM or CRM. It may be used to rejecta call if too many satellites are used. The circuit status indicates ifthe given circuit is idle, blocked, or not blocked. The circuit stateindicates the current state of the circuit, for example, active ortransient. The time/date indicates when the idle circuit went idle.

FIG. 11 depicts an example of the trunk group table. During originationprocessing, the trunk group number from the trunk circuit table is usedto key into the trunk table. Glare resolution indicates how a glaresituation is to be resolved. Glare is dual seizure of the same circuit.If the glare resolution entry is set to "even/odd," the network elementwith the higher point code controls the even circuits, and the networkelement with the lower point code controls the odd circuits. If theglare resolution entry is set to "all," the CCM controls all of thecircuits. If the glare resolution entry is set to "none," the CCMyields. The continuity control entry lists the percent of callsrequiring continuity tests on the trunk group.

The common language location identifier (CLLI) entry is a Bellcorestandardized entry. The satellite trunk group entry indicates that thetrunk group uses a satellite. The satellite trunk group entry is used inconjunction with the satellite indicator field described above todetermine if the call has used too many satellite connections and,therefore, must be rejected. The service indicator indicates if theincoming message is from a CCM (ATM) or a switch (TDM). The outgoingmessage index (OMI) points to the message table so that outgoingmessages can obtain parameters. The associated number plan area (NPA)entry identifies the area code.

Selection sequence indicates the methodology that will be used to selecta connection. The selection sequence field designations tell the trunkgroup to select circuits based on the following: least idle, most idle,ascending, descending, clockwise, and counterclockwise. The hop counteris decremented from the IAM. If the hop counter is zero, the call isreleased. Automatic congestion control (ACC) active indicates whether ornot congestion control is active. If automatic congestion control isactive, the CCM may release the call. During termination processing, thenext function and index are used to enter the trunk circuit table.

FIG. 12 depicts an example of the exception table. The index is used asa pointer to enter the table. The carrier selection identification (ID)parameter indicates how the caller reached the network and is used forrouting certain types of calls. The following are used for this field:spare or no indication, selected carrier identification codepresubscribed and input by the calling party, selected carrieridentification code presubscribed and not input by the calling party,selected carrier identification code presubscribed and no indication ofinput by the calling party, and selected carrier identification code notpresubscribed and input by the calling party. The carrier identification(ID) indicates the network that the caller wants to use. This is used toroute calls directly to the desired network. The called party numbernature of address differentiates between 0+ calls, 1+ calls, test calls,and international calls. For example, international calls might berouted to a pre-selected international carrier.

The called party "digits from" and "digits to" focus further processingunique to a defined range of called numbers. The "digits from" field isa decimal number ranging from 1-15 digits. It can be any length and, iffilled with less than 15 digits, is filled with 0s for the remainingdigits. The "digits to" field is a decimal number ranging from 1-15digits. It can be any length and, if filled with less than 15 digits, isfilled with 9s for the remaining digits. The next function and nextindex entries point to the next table which is typically the ANI table.

FIG. 13 depicts an example of the ANI table. The index is used to enterthe fields of the table. The calling party category differentiates amongtypes of calling parties, for example, test calls, emergency calls, andordinary calls. The calling party\charge number entry nature of addressindicates how the ANI is to be obtained. The following is the table fillthat is used in this field: unknown, unique subscriber numbers, ANI notavailable or not provided, unique national number, ANI of the calledparty included, ANI of the called party not included, ANI of the calledparty includes national number, non-unique subscriber number, non-uniquenational number, non-unique international number, test line test code,and all other parameter values.

The "digits from" and "digits to" focus further processing unique to ANIwithin a given range. The data entry indicates if the ANI represents adata device that does not need echo control. Originating lineinformation (OLI) differentiates among ordinary subscriber, multipartyline, ANI failure, station level rating, special operator handling,automatic identified outward dialing, coin or non-coin call usingdatabase access, 800\888 service call, coin, prison/inmate service,intercept (blank, trouble, and regular), operator handled call, outwardwide area telecommunications service, telecommunications relay service(TRS), cellular services, private paystation, and access for privatevirtual network types of service. The next function and next index pointto the next table which is typically the called number table.

FIG. 14 depicts an example of the called number table. The index is usedto enter the table. The called number nature of address entry indicatesthe type of dialed number, for example, national versus international.The "digits from" and "digits to" entries focus further processingunique to a range of called numbers. The processing follows theprocessing logic of the "digits from" and "digits to" fields in FIG. 12.The next function and next index point to the next table which istypically the routing table.

FIG. 15 depicts an example of the routing table. The index is used toenter the table. The transit network selection (TNS) networkidentification (ID) plan indicates the number of digits to use for theCIC. The transit network selection "digits from" and "digits to" fieldsdefine the range of numbers to identify an international carrier. Thecircuit code indicates the need for an operator on the call. The nextfunction and next index entries in the routing table are used toidentify a trunk group. The second and third next function/index entriesdefine alternate routes. The third next function entry can also pointback to another set of next functions in the routing table in order toexpand the number of alternate route choices. The only other entriesallowed are pointers to the treatment table. If the routing table pointsto the trunk group table, then the trunk group table typically points toa trunk circuit in the trunk circuit table. The yield from the trunkcircuit table is the terminating connection for the call.

It can be seen from FIGS. 14-19 that the tables can be configured andrelate to one another in such a way that call processes can enter thetrunk circuit table for the originating connection and can traversethrough the tables by keying on information and using pointers. Theyield of the tables is typically a terminating connection identified bythe trunk circuit table. In some cases, treatment is specified by thetreatment table instead of a connection. If, at any point during theprocessing, a trunk group can be selected, processing may proceeddirectly to the trunk group table for terminating circuit selection. Forexample, it may be desirable to route calls from a particular ANI over aparticular set of trunk groups. In this case, the ANI table would pointdirectly to the trunk group table, and the trunk group table would pointto the trunk circuit table for a terminating circuit. The default paththrough the tables is: trunk circuit, trunk group, exception, ANI,called number, routing, trunk group, and trunk circuit.

FIG. 16 depicts an example of the treatment table. Either the index orthe message received cause number are filled and are used to enter thetable. If the index is filled and used to enter the table, the generallocation, coding standard, and cause value indicator are used togenerate an SS7 REL. The message received cause value entry is the causevalue in a received SS7 message. If the message received cause value isfilled and used to enter the table, then the cause value from thatmessage is used in a REL from the CCM. The next function and next indexpoint to the next table.

FIG. 17 depicts an example of the message table. This table allows theCCM to alter information in outgoing messages. Message type is used toenter the table, and it represents the outgoing standard SS7 messagetype. The parameter is the pertinent parameter within the outgoing SS7message. The indexes point to various entries in the trunk group tableand determine if parameters can be unchanged, omitted, or modified inthe outgoing messages.

Those skilled in the art will appreciate that variations from thespecific embodiments disclosed above are contemplated by the invention.The invention should not be restricted to the above embodiments, butshould be measured by the following claims.

What is claimed is:
 1. A broadband system for connecting calls that usetime division multiplexing, the system comprising:a SONET ring adaptedto interconnect devices coupled to the SONET ring, the SONET ringcomprising SONET multiplexers coupled by SONET paths, wherein the SONETmultiplexers are adapted to add calls to, and drop calls from, the SONETring; an ATM cross connect system coupled to the SONET ring comprisingATM cross connect devices, the ATM cross connect devices adapted toprovide provisioned ATM connections over the SONET ring; a plurality ofATM interworking units coupled to the ATM cross connect system, the ATMinterworking units adapted to interwork calls with selected ATMconnections in response to control messages, wherein the selected ATMconnections are provisioned between selected ATM interworking units bythe ATM cross connect system over the SONET ring; and a signalingprocessor system adapted to receive call signaling for the calls, toprocess the call signaling to select the ATM connections for the calls,and to send the control messages to the selected ATM interworking unitsdesignating the selected ATM connections, to receive particular callsignaling for a particular call, to select a particular ATM connectionbetween a selected first ATM interworking unit and a selected second ATMinterworking unit for the particular call, to send a particular controlmessage to the selected first ATM interworking unit designating theparticular ATM connection, to select a particular TDM connection, and totransport a second control message to the selected second ATMinterworking unit designating the particular TDM connection; the ATMcross connect system is further adapted to provision the selectedparticular ATM connection between the selected first ATM interworkingunit and selected second ATM interworking unit over the SONET ring; andthe selected first ATM interworking unit is adapted to interwork theparticular call with the selected particular ATM connection; theselected second ATM interworking unit is adapted to receive the secondcontrol message from the signaling processing system, to receive thecall over the selected particular ATM connection, and to interwork thecall with particular TDM connection.
 2. The system of claim 1 whereinthe selected ATM connections are provisioned by the ATM cross connectsystem before calls are initiated.
 3. The system of claim 1 furthercomprising a communication device adapted to transport one of the callsthat is connected by the broadband system.
 4. The system of claim 3wherein the communication device comprises a local exchange carrier. 5.The system of claim 3 wherein the communication device comprises aninterexchange carrier.
 6. The system of claim 3 wherein thecommunication device comprises a service platform.
 7. The system ofclaim 3 wherein the communication device comprises a circuit-basedswitch.
 8. The system of claim 1 further comprising a communicationdevice adapted to receive one of the calls that is connected by thebroadband system.
 9. The system of claim 8 wherein the communicationdevice comprises a local exchange carrier.
 10. The system of claim 8wherein the communication device comprises an interexchange carrier. 11.The system of claim 8 wherein the communication device comprises aservice platform.
 12. The system of claim 8 wherein the communicationdevice comprises a circuit-based switch.
 13. The system of claim 1wherein user communications for calls are interworked by ATMinterworking units to ATM cells which are mapped to SONET frames, andwherein the ATM interworking units transport the SONET frames over theselected ATM connections.
 14. The system of claim 1 wherein the ATMinterworking units map SONET frames to ATM cells and interwork the ATMcells to non-ATM user communications.
 15. The system of claim 1 whereinthe broadband system comprises a metropolitan area network.
 16. Thesystem of claim 1 wherein the processing system comprises a plurality ofsignaling processors linked by links, wherein the signaling processorsare linked to the ATM interworking units and are adapted to send thecontrol messages to the ATM interworking units designating the ATMconnection.
 17. The system of claim 16 wherein the signaling processingsystem comprises a signal transfer point adapted to transfer callsignaling between the signaling processors.
 18. A broadband system forconnecting a call over a SONET ring that is adapted to interconnectdevices coupled to the SONET ring, the call having a time divisionmultiplex format and having user communications and call signaling, thesystem comprising:a SONET multiplexer coupled to the SONET ring, theSONET multiplexer adapted to add the call to the SONET ring; an ATMcross connect coupled to the SONET multiplexer, the ATM cross connectadapted to provide a provisioned ATM connection through the SONETmultiplexer over the SONET ring; an ATM interworking unit coupled to theATM cross connect, the ATM interworking unit adapted to interwork theuser communications with the ATM connection in response to a controlmessage, wherein the ATM connection is provisioned by the ATM crossconnect from the ATM interworking unit through the SONET multiplexerover the SONET ring; a signaling processor adapted to process the callsignaling to select the ATM connection for the call from among aplurality of connections and to send the control message to the ATMinterworking unit designating the ATM connection, to select a secondconnection and to transport a second control message designating thesecond connection; a second SONET multiplexer adapted to drop the callfrom the SONET ring; a second ATM cross connect adapted to provide theprovisioned ATM connection through the second SONET multiplexer; and asecond ATM interworking unit adapted to receive the call from the ATMconnection through the second SONET multiplexer and through the secondATM cross connect, to receive the second control message from thesignaling processor, to convert the call to user communications having asecond communication format, and to transport the user communicationsover the selected second connection.
 19. The system of claim 18 whereinthe provisioned ATM connection is provisioned by the ATM cross connectsystem before the call is initiated.
 20. The system of claim 18 furthercomprising a communication device adapted to transport the callsignaling to the signaling processor and to transport the usercommunications to the ATM interworking unit.
 21. The system of claim 18wherein the communication device comprises a local exchange carrier. 22.The system of claim 18 wherein the communication device comprises aninterexchange carrier.
 23. The system of claim 18 wherein thecommunication device comprises a service platform.
 24. The system ofclaim 18 wherein the communication device comprises a circuit-basedswitch.
 25. The system of claim 18 further comprising a communicationdevice adapted to receive the user communications in the secondcommunication format from the second ATM interworking unit over thesecond connection.
 26. The system of claim 25 wherein the communicationdevice comprises a local exchange carrier.
 27. The system of claim 25wherein the communication device comprises an interexchange carrier. 28.The system of claim 25 wherein the communication device comprises aservice platform.
 29. The system of claim 25 wherein the communicationdevice comprises a circuit-based switch.
 30. The system of claim 25wherein the broadband system comprises a metropolitan area network. 31.A broadband system for connecting a call over a SONET ring that isadapted to interconnect devices coupled to the SONET ring, the callhaving call signaling and user communications, the system comprising:asignaling processor adapted to receive the call signaling for the call,to process the call signaling to select an ATM connection for the call,to send a control message designating the selected ATM connection, toselect a second non-ATM connection, and to transport a second controlmessage designating the second non-ATM connection; an ATM interworkingunit adapted to receive the control message from the signalingprocessor, to receive the user communications, and to interwork the usercommunications for the call between a non-ATM connection and theselected ATM connection in response to the control message; a SONETmultiplexer adapted to provide access to the SONET ring for the selectedATM connection; and an ATM cross connect adapted to provision theselected ATM connection from the ATM interworking unit through the SONETmultiplexer over the SONET ring; wherein the call is transported overthe provisioned selected ATM connection from the ATM interworking unit,through the ATM cross connect, through the SONET multiplexer, and overthe SONET ring; a second SONET multiplexer adapted to drop the call fromthe SONET ring; a second ATM cross connect adapted to provide theprovisioned ATM connection through the second SONET multiplexer; and asecond ATM interworking unit adapted to receive the call from the ATMconnection through the second SONET multiplexer and through the secondATM cross connect, to receive the second control message from thesignaling processor, to convert the call to user communications having asecond communication format, and to transport the user communicationsover the selected second non-ATM connection.
 32. The system of claim 31further comprising a communication device adapted to transport the callsignaling to the signaling processor and the user communications to theATM interworking unit.
 33. The system of claim 31 further comprising acommunication device adapted to receive the user communications in thesecond communication format from the second ATM interworking unit overthe non-ATM connection.
 34. The system of claim 31 wherein the broadbandsystem comprises a metropolitan area network.
 35. A broadband system forconnecting a call having a time division multiplex format over abroadband ring, the call having call signaling and user communications,the system comprising:a signaling processor adapted to receive the callsignaling for the call, to process the call signaling to select aselected connection for the call from among a plurality of connections,to send the control message designating the selected connection, toselect a second connection, and to transport a second control messagedesignating the second connection; an add/drop multiplexer adapted toprovide the call access to the broadband ring; a cross connect adaptedto provision the selected connection through the add/drop multiplexerover the broadband ring; an interworking unit adapted to receive theuser communications and to receive the control message from thesignaling processor and, in response thereto, to interwork the usercommunications for the call to asynchronous transfer mode cells thatidentify the selected connection, to map the asynchronous transfer modecells to broadband frames, and to transport the broadband frames overthe selected connection; wherein the connection is provisioned by thecross connect from the interworking unit through the add/dropmultiplexer over the broadband ring; a second add/drop multiplexeradapted to drop the call from the broadband ring; a second cross connectadapted to provide the provisioned selected connection through thesecond add/drop multiplexer; and a second interworking unit adapted toreceive the call from the selected connection through the secondadd/drop multiplexer and through the second cross connect, to receivethe second control message from the signaling processor, to convert thecall to user communications having a second communication format, and totransport the user communications over the selected second connection.36. The system of claim 35 further comprising a communication deviceadapted to transport the call signaling to the signaling processor andthe user communications to the interworking unit.
 37. The system ofclaim 35 further comprising a communication device adapted to receivethe user communications in the second communication format from thesecond interworking unit over the second connection.
 38. The system ofclaim 35 wherein the broadband system comprises a metropolitan areanetwork.
 39. The system of claim 35 wherein the broadband systemcomprises a synchronous optical network system and wherein theasynchronous transfer mode cells are mapped to synchronous opticalnetwork frames in the interworking unit, and wherein the interworkingunit transports the synchronous optical network frames.
 40. The systemof claim 35 wherein the broadband system comprises a synchronous digitalhierarchy system and wherein the asynchronous transfer mode cells aremapped to synchronous digital hierarchy frames in the interworking unit,and wherein the interworking unit transports the synchronous digitalhierarchy frames.
 41. A system for connecting a call in a broadbandsystem, the call having user communications and call signaling, thesystem comprising:a first communication device adapted to transport thecall; a second communication device adapted to receive the call; asignaling processor adapted to receive the call signaling, to processthe call signaling to select a first connection and a second connection,to transport a first control message that designates the selected firstconnection, and to transport a second control message that designatesthe selected second connection, wherein the first selected connectioncomprises a virtual path over a broadband path, the virtual path beingprovisioned over the broadband path in the broadband system, and whereinthe selected second connection connects to the second communicationdevice; a first interworking unit adapted to receive the usercommunications in a communication format, to receive the first controlmessage from the signaling processor, to convert the user communicationsto asynchronous transfer mode cells that identify the selected firstconnection designated in the first control message, and to transport theasynchronous transfer mode cells; a first cross connect adapted toreceive the asynchronous transfer mode cells from the first interworkingunit and to cross connect the asynchronous transfer mode cells to thevirtual path for the selected first connection; a first add/dropmultiplexer adapted to receive the asynchronous transfer mode cells fromthe first cross connect and to add the asynchronous transfer mode cellsto the broadband path for the selected first connection; a secondadd/drop multiplexer adapted to receive the asynchronous transfer modecells on the broadband path and to drop the asynchronous transfer modecells from the broadband path; a second cross connect adapted to receivethe asynchronous transfer mode cells from the second add/dropmultiplexer and to cross connect the asynchronous transfer mode cellsaccording to the provisioned virtual path; and a second interworkingunit adapted to receive the asynchronous transfer mode cells from thesecond cross connect, to receive the second control message from thesignaling processor, to convert the asynchronous transfer mode cells touser communications having a communication format, and to transport theuser communications to the second communication device over the selectedsecond connection.
 42. The system of claim 41 wherein the broadbandsystem comprises a synchronous optical network system.
 43. The system ofclaim 42 wherein the asynchronous transfer mode cells are mapped tosynchronous optical network frames in the interworking unit, and whereinthe interworking unit transports the asynchronous transfer mode cellscontained in the synchronous optical network frames.
 44. The system ofclaim 41 wherein the broadband system comprises a synchronous digitalhierarchy system.
 45. The system of claim 44 wherein the asynchronoustransfer mode cells are mapped to synchronous digital hierarchy framesin the interworking unit, and wherein the interworking unit transportsthe asynchronous transfer mode cells contained in the synchronousdigital hierarchy frames.
 46. A system for connecting a call in abroadband system, the call having user communications and callsignaling, the system comprising:a signaling processor adapted toreceive the call signaling, to process the call signaling to select aconnection, and to transport a control message that designates theselected connection, wherein the selected connection comprises a virtualpath over a broadband ring in the broadband system, the virtual pathbeing provisioned over the broadband ring, and to select a secondconnection; a broadband interface adapted to receive the usercommunications in a communication format, to receive the control messagefrom the signaling processor, to interwork the user communications toasynchronous transfer mode cells that identify the selected connection,to map the asynchronous transfer mode cells to broadband frames, and totransport the broadband frames on the provisional virtual path over thebroadband ring; a second broadband interface adapted to receive thebroadband frames from the virtual path of the broadband ring and toremove the broadband frames from the broadband ring and comprising asecond add/drop multiplexer adapted to drop the broadband frames fromthe broadband ring, a second cross connect adapted to provision thevirtual path from the broadband ring through the add/drop multiplexer,and a second interworking unit adapted to receive the broadband framesfrom the add/drop multiplexer through the second cross connect, toreceive the second control message from the signaling processor, to mapthe broadband frames to the asynchronous transfer mode cells, to convertthe asynchronous transfer mode cells to the user communications having asecond communication format, and to transport the user communicationsover the selected second connection.
 47. The system of claim 46 whereinthe broadband interface comprises:an add/drop multiplexer adapted toprovide the call access to the broadband ring; a cross connect adaptedto provision the virtual path through the add/drop multiplexer over thebroadband ring; an interworking unit adapted to receive the controlmessage from the signaling processor and, in response, to interwork theuser communications for the call to asynchronous transfer mode cellsthat identify the selected connection, to map the asynchronous transfermode cells to broadband frames, and to transport the broadband framesover the selected connection; wherein the selected connection isprovisioned by the cross connect from the interworking unit through theadd/drop multiplexer over the broadband ring.
 48. The system of claim 46further comprising a communication device adapted to transport the callsignaling to the signaling processor and to transport the usercommunications to the broadband interface.
 49. The system of claim 46further comprising a communication device adapted to receive the usercommunications in the second communication format from the secondinterworking unit over the selected second connection.
 50. The system ofclaim 46 wherein the broadband system comprises a synchronous opticalnetwork system.
 51. The system of claim 46 wherein the broadband systemcomprises a synchronous digital hierarchy system.